Artificial arm.



S. A. NELSQN ARTIFICIAL ARM.

APPLICATION FILED Auc.27. I917.

Patented Nov. 19, 1918.

4 SHEETS-SHEET l nzyenzar S. A. NELSON.

ARTIFICIAL ARM.

APPLICATION man AUG-27, 1911.

Jay.

W M 9 W f/ s. 'A. NELSON.

ARTIFICIAL ARM.

APPLICATION FILED AUG.27, I917.

Patented Nov. 19. 191$.

4 sh: ETS-SHEET a.

S. A. NELSON;

'ARTlFlCiAL ARM.

APPLICATION FILED AUG.27. i917.

1,285,326. PatntedN0v.19,l918.

4 SHEETSSHEET 4.

SWAN A. NELSON, OF STROMSBURG, NEBRASKA.

AItTIFICIAL ARM.

Specification of Letters Patent.

Patented rim. 19, acre.

Application filed August 27, 1917. Serial No. 138,848.

To all whom it may concern Be it known that I, SWAN A. NELSON, a Citizenof the United States, residin at Stromsburg, in the county of Polk andtate of Nebraska, have invented certain new and useful Improvements inArtificial Arms, of which the following is a specification.

This invention relates to improvements in artificial limbs'and moreparticularly to an artificial arm adapted for attachment to the shoulderof the user. Thelimb comprises an upper varm t which a forearm .isadjustably secured, means being provided for locking the forearminlj-any adjusted position and for instantly releasing the forearm' fromsuch position whendesired,-said means being operable from'the shoulder.Further,

V the limb comprises axhand with integral fingers, said hand andfingersbeing stationary with relation to said forearm, said hand.

being provided with a movable thumb controlled by a slight movementof'the wearers' chest about which a portion of-the supporting harnessextends, connection between-the harness and thumbbeingprovided. Morespecifically the invention consists in the combination and arrangementof parts to be hereinafter fully described, pointed out in the appendedclaims and illustrated in the accompanying drawings which form a part ofthis. specification and in which Figure l is a sideelevation of myartificial limb, the dotted lines showing the forearm in raisedposition.

Fig. 2 is a fragmentary plan view of the arm, the elbow joint beingexposed to alfor a better illustration.

Fig. 3 is a longitudinal sectional view I through Fig. 2.

Fig. 4 is a fragmentary sectional view of 'the lower part of the limbshowing the operating mechanism for the thumb.

Fig. 5 is a cross section taken on llne 55 be Fig. 2..

Fig. 6is a crosssection on line 66 of 2 with some parts removed.

Fig. 7 is a plan view of Fig. 4.

Like reference characters denote corresponding parts throughout theseveral views.

My. invention includes an up'per arm having a core 1, preferablv of woodor cork and provided with a leather covering 2 which is open in thefront and provided with eyelets 3 by means of which, and the cord 4:, itmay be laced shut. The'upoer end of the covering 2 is formed with ears 5to whlchthe harness 6 is secured, said harness being adapted to passacross the back and chest of the user and under the arm upon theopposite side of the body to which my arm is attached. A brace-strap 7connects the front of the covering 2 with one ear 5 and the.

harness 6. The said 'core 1 extends beyond the lower terminationof thecovering 2 and is bifurcated at its lower end and transversely throughsaid bifurcated end the elbow pivot 8 extends, said. pivot connecting vthe forearm 9 to the upper arm, the ends of said elbow pivot connectingthe longitudinal bands 10 of the upper arm, pivotally, with thelongitudinal bands 11 of the forearm;

The upper termination of the forearm is hollow and open to permit accessto its interior, the open portion of the forearm as well as thebifurcated portion ofthe upper 'arm being covered by a flexible sheet12.

The forearm terminates in a hand 13, the

fingers 14 of which are relatively stationary, said hand being providedwith a. thumb 15.

A spring -16 connects the wall 17 of the thumb with the post- 23toyieldingly retain the thumb in frictional engagement with a finger 14.

The pivoted end of the thumb is provided 3 with a toothed segment 20 inmesh with a toothed segment 21 formed terminally of-a' link 22 connectedby pivot 23 to a-stay-plate 24 arranged in the hand 13, said stay platebeing connected by'screws 25' passing to the hand. The said link. 22 isformed with a perforation 26 in one end to permit its engagement by alink 2'? to which a cord 28 is secured, said cord passing through the-fore arm and over a sleeveor roller 29' arranged upon a shaft 30, saidsleeve 29 also carrying a disk 31 .whichserves as a guide for the cord28 to limit its lateral movement within the forearm. Beyond the sleeve29 the cord 28passes over a guide roller 32 and through the bifurcatedend of a fork 33, said forkend carrying the shaft 34 of the said guideroller 32 and said fork being secured by fastening means'35 to thecore 1. 28 extends over a guide roller 36 of rollershaft 37 disposed ina recess 38 formed in the core 1, said roller-shaft being journaicd inthe said core, and beyond said roller the cord passes out between thesheet 12 and covering 2 and over a guide-roller 39, car ried by saidcovering, to the harness 6 to which it is secured.

The cord 1 Adjacent the inner face ofone prong of I the bifurcated endof the core 1 I provide a sheave i0 which is centered but loose upon theelbow pivot 8, said sheave being carried by all arm ilfast to the shaft30 and said sheave being formed with one lateral flange -l2 that extendsbeyond the periphery of said sheave and thatsp aces said member awayfrom'the adjacent prong of the core 1. The said-sheave, further, isformed with an integral toothed segment d3 of smaller diameter than thesheaveitself, said segment being adapted normally for locking engagementwith a dog all fulcrumed uponthe elbow pivot 8, said dog beingyieldingly retained in engagement with the segme 1t 43 by means of anexpansion spring 45 arranged upon the shaft. 8 and abutting said dog andthe core 1. The dog is formed with the ears 46 to which the strap 47 'issecured that. extends out through an opening48, in which is arranged a'pulley 4:8, in the core 1 and through a guide ring 49, carried by thecovering 2, to the harness 6 to which it is secured.

A hook 50 fast to the shaft 30 is engaged by a cord 51 which passes overthe sheave 40 and out through a. perforation 51 in which is arranged aroller 51'. in the core 1 and up through guide-loops 52 to the harness,one guide-loop-strap being connected by a spring 53 t the brace-strap 7.To op-. erate the thumb-15 againstthe tension of its spring the operatorexpands his chest to cause a pull upon the strap 28 which will move thelink 22 upon its pivot and so move the thumb away from the fingers l l.When the tension upon the strap 28 i relaxed the spring will again movethe thumb into frictional engagement with the fingers. I To move theforearm upon the elbow pivot the operator raises his shoulder adjacentthe limb to cause a pull upon the strap 47, the strap being adjusted toclosely fit the shoulder, which will withdraw the dog 41 from lockingengagement with the segment 43, a

' further shoulder movement will now cause the strap 51 to raise orlower the forearm as desired. A- forward movementof the. shoulder willdrop the forearm and a back movement of the shoulder will raise theforearm and when the shoulder is lowered to normal position the spring45 will force the dog into engagement with the segment 43 again lockingthe arm'in adjusted position. The first shoulder movement is always anupward movementto effect release of the dog from its segment'and thesecond shoulder movement i a forward or backward movement to lower orraise the forearm asdesired. With a little practice the user will becomeadept in effecting the arm and thumb movements described.

\Vhat is claimed is 1, In an artificial armincluding a hand member, anarm-supporting harness adapted to be fitted to and movable with apersons shoulders and chest, a thumb pivotally supported by said hand,means connecting said thumb and hand for yieldingly retainally securedto said hand, and flexible means connecting said lever and the saidharness whereby movement of the latter due to expansion and contractionof a persons chest will operate to actuate said lever.

2. In an artificial arm including a hand member,- an arm-supportingharness adapted to be fitted to and movable with a persons shoulders andchest, a thumb pivotally se-' cured to said hand, a toothed segmentterminating said thumb, a spring connecting said thumb and hand foryieldingly retainmg said thumb with frictional engagement with one ofthe fingers of said hand, a toothed lever pivotally secured to said handand in operative engagement with said seglever and the said harnesswhereby move ment of the latter due to expansion and contraction of apersons' CllGSL- will actuate said lever.

3. Inan artificial arm, anupper arm, a supporting harness for said upperarm adapted to be fitted to and movable with a persons shoulders andchest, a forearm, an elbow pivot connecting said upper arm and forearm,a toothed segment movably centered upon said elbow pivot, a dog carriedupon said elbow pivot for releasable locking engagement with saidsegment, control means for said dog connecting the same and saidharness, and means connecting said forearm and harness whereby movementof the. latter may be transmitted to said forearm.

4. In an artificial arm, an upper arm, a supporting harness for saidupper arm adapted to be fitted to and movable with a v persons shouldersand chest, a forearm, an

elbow pivot connecting said upper arm and forearm, a transverse shaftcarried, by said forearm, a toothed segment carried by said transverseshaft and associated with said elbow pivot, a dog carriedfupon saidelbow pivot for releasable locking engagement with said segment, controlmeans for said dog connecting the same and said harness, andfiexible'means connecting said forearm and harness whereby movement ofthe latter may be transmitted to the former.

5. In an artificial arm, an upper arm, a supporting harness for saidupper arm adapted to be fitted to and movable with a persons shouldersand chest, a forearm, an elbow pivot connecting said upper arm andforearm, a transverse shaft carried by said forearm, a sheaveoperatively supported by said transverse shaft and associated with saidelbowpivot, a toothed segment integral -ment, and flexible connectionbetween said i with said sheave, a dog carried by said elbow as my own Ihave hereto afiixed my "Signapivot, f0rreleasable locking engagementture in the presence of two subscribing witwith said segment, andflexible means for messes. connecting said harness and transverse shaftSVAN A; NELSON. 5 wherebymovement of said harness may be \Vit nesses:.transmitted to said forearm. Josnrn HEADMAN,

In testimony that I. claim the foregoing BERNARD Wwramr,

